The real question is whether you can work in this style. It's tricky, which is why I can't make proper textures- only placeholder ones. If you think you can draw in this style though, let me know. I'd love some more help.
There isn't one, per se. However, the 1.14 version should work mostly well in 1.12, as the only real change between those versions were new blocks and the villagers. Since we never removed the old villagers, they should still work. If they do, let me know.
Ah right, I remember that. Okay, so renaming the block and item folders should be easy enough, but all of the models will be broken. To fix those, you can open the model files in notepad or something individually and change block to blocks and such. It's a lot of work, but if you do come up with a finished product, send it to me and I'll put it up for download with the other versions, if that's okay with you.
I have a question for you guys. Do you think that netherite tools should simply be visually upgraded versions of the diamond tools, or should they be new tools entirely. Let me know in this poll what your opinions are.